Suturing of tissue during surgical procedures is time consuming and can be particularly challenging in difficult to access body regions and regions that have limited clearance, such as regions partially surrounded or covered by bone. For many surgical procedures, it is necessary to make a large opening in the human body to expose the area requiring surgical repair. However, in many cases, accessing the tissue in this manner is undesirable, increasing recovery time, and exposing the patient to greater risk of infection.
Suturing instruments (“suture passers” or “suturing devices”) have been developed to assist in accessing and treating internal body regions, and to generally assist a physician in repairing tissue. Although many such devices are available for endoscopic and/or percutaneous use, these devices suffer from a variety of problems, including limited ability to navigate and be operated within the tight confines of the body, risk of injury to adjacent structures, problems controlling the position and/or condition of the tissue before, during, and after passing the suture, as well as problems with the reliable functioning of the suture passer.
For example, some surgical instruments used in endoscopic procedures are limited by the manner in which they access the areas of the human body in need of repair. In particular, the instruments may not be able to access tissue or organs located deep within the body or that are in some way obstructed. In addition, many of the instruments are limited by the way they grasp tissue, apply a suture, or recapture the needle and suture. Furthermore, many of the instruments are complicated and expensive to use due to the numerous parts and/or subassemblies required to make them function properly. Suturing remains a delicate and time-consuming aspect of most surgeries, including those performed endoscopically.
For example, some variations of suture passers, such as those described in U.S. Pat. No. 7,377,926 to Taylor, have opposing jaws that open and close over tissue. One, or in some variations, both, jaws open, scissor-like, so that tissue may be inserted between the open jaws. Unfortunately, such devices cannot be adequately positioned for use in hard to navigate body regions such as the joints of the body, including the knee (e.g., meniscus) and the shoulder.
The meniscus is a C-shaped piece of fibrocartilage which is located at the peripheral aspect of the joint (e.g., the knee) between the condyles of the femur and the tibia on the lateral and medial sides of the knee. The central two-thirds of the meniscus has a limited blood supply while the peripheral one third typically has an excellent blood supply. Acute traumatic events commonly cause meniscus tears in younger patients while degenerative tears are more common in older patients as the menisci become increasingly brittle with age. Typically, when the meniscus is damaged, a torn piece of meniscus may move in an abnormal fashion inside the joint, which may lead to pain and loss of function of the joint. Early arthritis can also occur due to these tears as abnormal mechanical movement of torn meniscal tissue and the loss of the shock absorbing properties of the meniscus lead to destruction of the surrounding articular cartilage. Occasionally, it is possible to repair a torn meniscus. While this may be done arthroscopically, surgical repair using a suture has proven difficult to perform because of the hard-to-reach nature of the region and the difficulty in placing sutures in a way that compresses and secures the torn surfaces.
Arthroscopy typically involves inserting a fiberoptic telescope that is about the size of a pencil into the joint through an incision that is approximately ⅛ inch long. Fluid may then be inserted into the joint to distend the joint and to allow for visualization of the structures within that joint. Then, using miniature instruments which may be as small as 1/10 of an inch, the structures are examined and the surgery is performed.
The meniscus of the knee is just one example of a tissue that is difficult to access so that appropriate suturing may be performed. FIGS. 1A, 1B and 2 illustrate the anatomy of the meniscus in the context of a knee joint. As shown in FIG. 2 the capsule region (the outer edge region of the meniscus) is vascularized. Blood enters the meniscus from the menisculocapsular region 211 lateral to the meniscus. A typical meniscus has a flattened bottom (inferior surface or side) and a concave top (superior surface or side), and the outer cross-sectional shape is somewhat triangular. The outer edge of the meniscus transitions into the capsule. FIG. 3 illustrates the various fibers forming a meniscus. As illustrated in FIG. 3, there are circumferential fibers extending along the curved length of the meniscus, as well as radial fibers, and more randomly distributed mesh network fibers. Because of the relative orientations and structures of these fibers, and the predominance of circumferential fibers, it may be beneficial to repair the meniscus by suturing radially (vertically) rather than longitudinally or horizontally, depending on the type of repair being performed.
For example, FIGS. 4A-4E illustrate various tear patterns or injuries to a meniscus. Tears may be vertical/longitudinal (FIG. 4A), oblique (FIG. 4B), degenerative (FIG. 4C), including radially degenerative, transverse or radial (FIG. 4D) and horizontal (FIG. 4E). Most prior art devices for suturing or repairing the meniscus are only capable of reliably repairing vertical/longitudinal tears. Such devices are not typically useful for repairing radial or horizontal tears. Furthermore, prior art device mechanisms have a high inherent risk for iatrogenic injury to surrounding neurovascular structures and chondral surfaces.
Thus, there is a need for methods, devices and systems for suturing tissue, particularly tissue in difficult to access regions of the body including the joints (shoulder, knee, etc.). In particularly, it has proven useful to provide a device that may simply and reliably reach and pass sutures within otherwise inaccessible tissue regions. Such devices should be extremely low profile. Finally, it is useful to provide suturing devices that allow selective and specific penetration of the tissue by both the tissue penetrator (needle element) and a jaw so that complex (including right-angled) suturing patterns may be achieved. The methods, devices and systems described herein may address this need.